Receiving device for electric waves



' F. SCHNEIDER RECEIVING DEVICE FOR ELECTRIC WAVES Filed Novl ;e, 1921 Patented lib-l, 1%25.

OFFICE.

FERDINAND SCHNEIDER, OF FULDA, GERMANY.

RECEIVING DEVICE FOR ELECTRIC WAVES.

Application filed November 16, 1921.

To all whom it may concern:

Be it known that I, FERDINAND SCENE} DER, residing at Fulda, Germany, 16 Balinhausstrasse, have invented certain new and useful Improvements in Receiving Devices for Electric Waves, of which the following is a specification.

This invention relates to that class of receiving devices for damped or undamped electric waves, in whicha gap between elec trodes is bridged over by means of a preferably spherical member of wave-reactive material, i. e. a crystalline substance which 1s responsive or sensitive to electric waves, for example, silicon, molybdenum glance, pyrites, carborundum or the like, said wavereactive member being subjected to pressure. I

I have found that members composed of such wave-reactive material have not a uniform sensitiveness throughout and therefore I make said members movable along the electrode gap, preferably by means of rotation around their centres, this insures that the most sensitive points'of the wave-reactive member or members can be brought in contact with the electrodes.

Another feature of'my invention consists therein that the pressure exerted on the wave-reactive member or members is made adjustable whereby the efiect may be in creased. By roughening the edges of the electrodes in contact with the wave-reactive member, or by bending electrodes of sheet metal, I increasethe number of points of contact and finally I form the wave-reactive member or members from the most wavesensitive parts of the reactive substance, which parts I ascertain by previous experiment. By this means the specific resistance is considerably reduced, so that weak-current relays connected up can be used without the hitherto necessary intensifiers or extra sources of current, because speeches or sounds are received with a more powerful and absolutely clear tone.

In the various typical embodiments of the receiving device according to the drawing illustrating this invention, Fig. 1 is a side elevation of the receiving device Figs. 2 and 3 are plan views of electrodes arranged concentrically and eccentrically one within another forming a uniform gap and a gap of decreasing width; Figs. 4; and 5 are vertical sections through electrodes arranged one within another but having gaps of differgnt sectional. shape; Fig. 6 is a sim? Serial No. 515,468.

ilar section through an embodiment in' which the pressure plate of the wave reactive member serves as an electrode; Fig. 7 is a similar section with the wave reactive members held in position by means of a carrier disc, without the application of pressure; Figs. 8, 9 and 10 show electrodes arranged side by side, with linear gaps, in side elevation and plan respectively, and Fig. 11 is a vertical sectlon through an embodiment in which a second analogous electrode system, is arranged above the first electrode system on the pressure plate.

As can be seen from Fig. 1 a bearing yoke 32 is secured on the insulation plate a, and in this plate a are inserted the plugs 0, d, which are in conductive connection with the screws 6, 7. These latter traverse the plate a and serve to secure the electrodes 9, h, ar ranged one within another and resting on said plate. The bushing z, provided with a flange, is rotatably mounted in the bore s of the bearing yoke b, and is held in position by the retaining spring 7, which engages in the groove t and is secured to the yoke 19. In the longitudinal bore of thebushing 0'. slides the shaft of the circular pressure disc m of insulating material, the ascent and descent of which is restricted by the pin n in the shaft of the disc m engaging a slot Z of the bushing 2'. In the bushing i and above the shaft lies the spiral pressure spring 0 the tension of which can be adjusted by the screw p which is let into the head of the bushing. A disc 9 secured on the upper end of the bushing 2', enables the bushing 11 to be rotated by hand, and with it the disc m. The electrodes '9, h are separated by the gap to, which is conductively bridged over by the spherical wave reactive member is under the'pressure of the disc m. The conductors u, o are connected to the plugs 0, d. In Fig. 2 the gap to is of uniform width all the way round, but in Fig. 3 it is of decreasing width towards one side. The gap to may have a rectangular edge (Fig. 4:) or be beveled (Fig. 5).

In the embodiment according to Fig. 6, the electrode 9 has a groove of semicircular cross section on its upper surface and the disc m is arranged as the counter electrode, being connected to the conductor '0. In this case three points of unilateral conductivity come into operation, two on the grooved electrode 9 and one on the counter-electrode m, If the latter is also pro ided with a,

groove a fourth point of unilateral conductivity is obtained. In the embodiment according to Fig. 7 the gap to is bridged. over by two spheres is subjected only to their own weight, and the disc at holds the spheres in in two apertures even when th y shifted on the gap w by the rotation of the disc m.

In the embodiment according to Figs. 8 and 9, the electrodes 9, h consist of two rods arranged side by side, which may also be of disc shape and, as shown in Fig. 10, be employed in larger number. Here the electrodes g, h, 9 form the double gap 10-20, which is bridged over by two spheres 7c. The electrodes 9, g are jointly connected to the conductor a, whilst the electrode h 15 connected to the conductor o. The electrodes whether constructed as rods or discs may also be arranged obliquely in relation to each other, instead of parallel, thus making the gap or gaps w, convergent. Of course, means for pressing the spheres could also be provided in these cases and such means could also be differently arranged from that shown in Fig. 1.

In the embodiment according to Fig. 11, circular double electrodes 9, h, g, h with double gaps, w, w and two spheres 7c, are employed, the circular insulating disk 03, to which is fi'mly secured the upper external electrode h, being secured to the disc m. In this case the upper and lower electrodes g, g are jointly connected to the conductor u, and the upper and lower electrodes h are jointly connected to the conductor 0); and the opposed double electrodes 9, 7L and the double gap w act with the spheres 70 as multiple contacts.

Of course, the essential features of the invention are not affected if the members 9, h are made of wave reactive material and the spheres 7a of metal, or other suitable counter-electrode material. The wave reactive members 76 may, of course, have other shapes than spherical.

The receiving device according to the invention operates in the following manner. On the reception of the electric waves these latter pass through the conductors u, 0, e and o, d,- f (Fig. 1) to the two electrodes 9 and h. Since the gap w is closed by the spherical wave reactive member 7a, the disconnected oscillation circuit is also completed; and since the spheres 7c establish contact, by their periphery, with the edges of the electrodes at two points, the current appears at both points of contact, which current can'be utilized for operating a relay, or for receiving audible or written Morse signals or for telephony or the audible reception of sounds. The contact pressure of the sphere 70 must be adjusted according to the rectifying medium selected. By turning the disc m by means of the disc 9, the sphere is is rotated, and rolls in the gap w to the position of the desired maximum of unilateral conductivity. The unilateral conductivity can also be increased by making the electrodes g, it of, sheet material with turned-up edges, the points of contact with the sphere 70 being increased by the alteration in structure or surface of the edges.

The unilateral conductivity may be similarly increased by roughening the edges of the electrodes. A further increase in sensit-iveness may be obtained by the employment of a gap of decreasing width according to Fig. 3 for example. When the sphere lies over the narrowest portion of the gap w, the maximum degree of sensitiveness is obtained, and at the same time the specific resistance of the receiver contacts is considerably reduced. The material of which the spherical rectifying member is composed naturally plays an important part. If a highly sensitive crystal be used as such in order to obtain a high efliciency, a single sphere will give the desired effect. By using several spheres, even with crystals hitherto considered as of low sensitiveness, a high efliciency is obtained combined with diminished specific resistance.

I claim:

1. A receiving device for damped and undamped electric waves consisting of electrodes leaving an intermediate gap, a spherical electric wave reactive member bridging over said electrode-gap and a means for moving said member along said gap imparting to it a rotation around its centre.

2. A. receiving device for electric waves consisting of an annular electrode surrounding a circular electrode so as to leave an intermediate gap, a member reactive to electric waves bridging over said gap and a means for moving said member along said gap.

3. A receiving device for electric waves consisting of electrodes leaving an intermediate gap bridged over by a member reactive to electric waves and adapted to be moved along said gap and a rotatable disc holding said member and imparting to it said movement.

4. A. receiving device for electric waves consisting of electrodes leaving an intermediate gap bridged over by a spherical member reactive to electric waves and adapted to be moved along said gap and a rotatable means standing under adjustable pressure of a spring for imparting said movement to said member.

5. A receiving device for electric waves consisting of electrodes leaving an intermediate ga p, bridged over by a member reactive to electric waves and adapted to be moved along said gap and a rotatable disc standing under adjustable pressure of a spring for imparting said movement and said pressure to said member.-

6. A receiving device for electric waves consisting of electrodes leaving an intermediate gap bridged over by a member reactive to electric Waves and adapted to be moved along said gap, a rotatable disc standing under adjustable pressure of a spring for imparting said movement to said member, and a means for rotating said disc.

7 A receiving device for electric waves consisting of a circular electrode in fixed position, an annular electrode in fixed position surrounding said circular electrode so as to leave an intermediate gap, a spherical member reactive to electric Waves bridging over said gap, a rotatable disc resting on said member and provided with a shaft slidably mounted Within a cylinder and engaging a slot of said cylinder by a laterally projecting pin, said cylinder being turnable with said shaft in a yoke, a screw-threaded spring Within said cylinder above said shaft and a screw screwed in the upper end of said cylinder for adjusting the pressure of said spring on said shaft.

In testimony whereof I ailix my signature.

FERDINAND SCHNEIDER. 

